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991.
Pathogenic variants in the X‐linked gene ZC4H2, which encodes a zinc‐finger protein, cause an infrequently described syndromic form of arthrogryposis multiplex congenita (AMC) with central and peripheral nervous system involvement. We present genetic and detailed phenotypic information on 23 newly identified families and simplex cases that include 19 affected females from 18 families and 14 affected males from nine families. Of note, the 15 females with deleterious de novo ZC4H2 variants presented with phenotypes ranging from mild to severe, and their clinical features overlapped with those seen in affected males. By contrast, of the nine carrier females with inherited ZC4H2 missense variants that were deleterious in affected male relatives, four were symptomatic. We also compared clinical phenotypes with previously published cases of both sexes and provide an overview on 48 males and 57 females from 42 families. The spectrum of ZC4H2 defects comprises novel and recurrent mostly inherited missense variants in affected males, and de novo splicing, frameshift, nonsense, and partial ZC4H2 deletions in affected females. Pathogenicity of two newly identified missense variants was further supported by studies in zebrafish. We propose ZC4H2 as a good candidate for early genetic testing of males and females with a clinical suspicion of fetal hypo‐/akinesia and/or (neurogenic) AMC.  相似文献   
992.
The karyotype is a strong independent prognostic factor in myelodysplastic syndromes (MDS). Since the implementation of the new comprehensive cytogenetic scoring system for MDS, chromosome 7 anomalies are no longer generally assigned to poor risk features but are thoroughly separated. However, der(1;7)(q10;p10), hereinafter der(1;7), is merged into the group labeled “any other single” and belongs to the intermediate risk group, just by definition due to lack of adequate clinical data. The aim of our international collaborative was to clarify the “real” prognostic impact of der(1;7) on a homogenous and well‐documented data base. We performed detailed analysis of 63 MDS patients with isolated der(1;7) constituting the largest cohort hitherto reported. Furthermore, clinical data are compared with those of patients with isolated del(7q) and isolated monosomy 7. Median overall survival (OS) of patients with der(1;7) is 26 months (hazard ratio (HR) 0.91 for del(7q) vs der(1;7) and 2.53 for monosomy 7 vs der(1;7)). The der(1;7) is associated with profound thrombocytopenia most probably causing the reduced OS which is in striking contrast to the low risk for AML transformation (HR 3.89 for del(7q) vs der(1;7) and 5.88 for monosomy 7 vs der(1;7)). Molecular karyotyping indicates that der(1;7) is generated in a single step during mitosis and that a chromosomal imbalance rather than a single disrupted gene accounts for malignancy. Thus, the current cytogenetic scoring system assigning isolated der(1;7) to the intermediate risk group is now confirmed by a sufficient data set.  相似文献   
993.
The University of North Carolina at Chapel Hill has established an extensive randomized trial to evaluate early treatment of Class-II/1 cases. As presented in this part of the study, a German treatment group was selected in parallel, based on identical prospective criteria, in the context of international cooperation with the Westfälische Wilhelms-Universität, Münster. One essential aspect of this study is the degree to which initially comparable groups can be established by careful alignment of selection criteria and of compilation and analysis of diagnostic records.Nine skeletal analysis parameters initially indicated that it is possible to select very similar though not absolutely identical groups in the context of international cooperation. The further results of the initial 15-month phase comprising functional orthodontic treatment in severe Class-II/1 cases showed significant mandibular effects in both treatment groups (USA UNC, Chapel Hill: modified Balters appliance; Germany WWU Münster: U-bow activator Type I). The groups were compared to a randomized control group with similar untreated malocclusions, established at Chapel Hill (USA UNC, Chapel Hill).  相似文献   
994.
Hepatitis B viruses specifically target the liver, where they efficiently infect quiescent hepatocytes. Here we show that human and avian hepatitis B viruses can be converted into vectors for liver-directed gene transfer. These vectors allow hepatocyte-specific expression of a green fluorescent protein in vitro and in vivo. Moreover, when used to transduce a type I interferon gene, expression of interferon efficiently suppresses wild-type virus replication in the duck model of hepatitis B virus infection. These data suggest local cytokine production after hepatitis-B-virus-mediated gene transfer as a promising concept for the treatment of acquired liver diseases, including chronic hepatitis B.  相似文献   
995.
Human granulocytotropic ehrlichias are tick-borne bacterial pathogens that cause an acute, life-threatening illness, human granulocytic ehrlichiosis (HGE). Ehrlichias within neutrophil granulocytes that invade tick bite sites are likely ingested by the vector, to be transmitted to another mammalian host during the tick's next blood meal. Thus, the cycle of replication and development in the vector is prerequisite to mammalian infection, and yet these events have not been described. We report tick cell culture isolation of two strains of the HGE agent directly from an infected horse and a dog and have also established a human isolate from HL60 culture in tick cells, proving that the blood stages of the HGE agent are infectious for tick cells, as are those replicating in the human cell line HL60. This required changes to the culture system, including a new tick cell line. In tick cell layers, the HGE agent induced foci of infection that caused necrotic plaques and eventual destruction of the culture. Using the human isolate and electron microscopy, we monitored adhesion, internalization, and replication in vector tick cells. Both electron-lucent and -dense forms adhered to and entered cells by a mechanism reminiscent of phagocytosis. Ehrlichial cell division was initiated soon after, resulting in endosomes filled with numerous ehrlichias. During early development, pale ehrlichias with a tight cell wall dominated, but by day 2, individual bacteria condensed into dark forms with a rippled membrane. These may become compacted into clumps where individual organisms are barely discernible. Whether these are part of an ehrlichia life cycle or are degenerating is unknown.  相似文献   
996.
Recently, we reported successful transplantation (Tx) of microencapsulated (mc) islets. However, graft failure observed in several cases was associated with an increased foreign body reaction compared to long-term functioning grafts. This study was performed to investigate the impact of an immunoalterating islet pretreatment (12–14 days culture at 22°C) on graft function. After microencapsulation in barium alginate beads the islets were cultured for another day. Diabetic LEWIS rats (blood glucose >19 mM) were transplanted with 3500 immunoaltered mc-Wistar islets intraperitoneally. Controls were transplanted with 3500 non-cultured syngeneic or allogeneic mc-islets. Additional syngeneic and allogeneic controls were transplanted with 6000 non-cultured, non-encapsulated islets intraperitoneally. Seventy percent of the recipients of microencapsulated, long-term low temperature cultured islets maintained normoglycemia at least for 15 weeks, while this was true in only 17% of those animals receiving microencapsulated non-pretreated allogeneic islets. Islets in non-encapsulated controls were rejected within several days. Graft function correlated with histologically proven viable islets within the capsules. Microencapsulation of islets markedly prolonged allograft survival compared to non-encapsulated islets; application of an immunoaltering low-temperature culture further improved graft function significantly. These data may support the hypothesis of induction of a reaction against microcapsules by the antigen release from the graft which may be avoided by immunoaltering islet pretreatment.  相似文献   
997.
Calciphylaxis is a rare syndrome mostly affecting patients with secondary hyperparathyroidism and in some cases with functional protein C or protein S deficiency. Skin lesions begin as superficial painful patches that progress to deep necrotic lesions. The findings are often misdiagnosed as livedo vasculitis and the prognosis is poor. Histopathologically, calcification in the media of small arteries and arterioles with intimal hyperplasia is seen. It is unclear if this morphologic hallmark is pathogenetic. Therapeutically, the calcium-phosphate product should be lowered pharmacologically by an intensified and modified dialysis treatment and parathyroidectomy.  相似文献   
998.
Zusammenfassung Im Bereich der adjuvanten Therapie des malignen Melanoms nimmt Interferon-alpha (IFN-α) eine wichtige Stellung ein. Unter den unerwünschten Nebenwirkungen spielen in der Langzeitbehandlung zunehmend psychische Ver?nderungen eine Rolle, insbesondere bei Therapieabbrüchen. Bekannt sind Schlafst?rungen, Unruhezust?nde, dauernde Müdigkeit, erh?hte Ersch?pfbarkeit, zunehmende Reizbarkeit, sozialer Rückzug und depressive Verstimmungen, die zumeist in den ersten drei Monaten der Behandlung entstehen. Aber auch schwerwiegende Nebenwirkungen wie delirante Zust?nde, schwere organische Depressionen, psychotische Episoden und organische Wesens?nderungen k?nnen sich unter der Behandlung entwickeln und sogar zu Suizidversuchen führen. Anhand zweier Fallbeispiele werden Entstehungsm?glichkeiten suizidaler Syndrome unter der Therapie mit IFN-α verdeutlicht. Therapeutisch bieten sich je nach Schwere der Nebenwirkungen neben einer Dosisreduktion oder Behandlungsunterbrechung kurzfristig Benzodiazepine an. Gute Erfahrungen konnten bei leichten bis mittelschweren depressiven Syndromen mit Antidepressiva aus der Klasse der Serotonin-Wiederaufnahmehemmer gemacht werden, so da? unter Umst?nden eine Therapieunterbrechung vermieden werden kann. Bei schweren depressiven Syndromen oder organischen Wesens?nderungen sollte prim?r die Behandlung mit IFN-α abgesetzt und bei Verdacht auf Suizidalit?t eine station?r-psychiatrischer Behandlung erwogen werden. Eingegangen am 29. Oktober 1998 Angenommen am 10. M?rz 1999  相似文献   
999.
The identification of genes with increased expression in vivo may lead to the identification of novel or unrecognized virulence traits and/or recognition of environmental signals involved in modulating gene expression. Our laboratory is studying an extraintestinal isolate of Escherichia coli as a model pathogen. We had previously used human urine ex vivo to identify the unrecognized urovirulence genes guaA and argC and to establish that arginine and guanine (or derivatives) were limiting in this body fluid (T. A. Russo et al., Mol. Microbiol. 22:217-229, 1996). In this study, we have continued with this approach and identified three additional genes that have increased expression in human urine relative to Luria-Bertani (LB) medium. Expression of ure1 (urine-responsive element) is increased a mean of 47.6-fold in urine but completely suppressed by exogenous glucose. This finding suggests that ure1 is regulated by catabolite repression and that limiting glucose in urine is a regulatory signal. ure1 is present in the E. coli K-12 genome, but its function is unknown. Although disruption of ure1 results in diminished growth in human urine, limiting concentrations of amino acids, nucleosides, or iron (Fe), or changes in osmolarity or pH do not affect the expression of ure1. Therefore, Ure1 appears to have a role independent of the synthesis or uptake of these nutrients and does not appear to be involved in osmoprotection. iroN(E. coli) is a novel E. coli gene with 77% DNA homology to a catecholate siderophore receptor gene recently identified in Salmonella. Its expression is increased a mean of 27.2-fold in urine and is repressed by exogenous Fe and a urinary pH of 5.0. This finding supports the contention that Fe is a limiting element in urine and that alteration of pH can affect gene expression. It is linked to the P-pilus (prs) and F1C fimbrial (foc) gene clusters on a pathogenicity island and appears to have been acquired by IS1230-mediated horizontal transmission. The homologous iroN(E. coli) sequence is significantly more prevalent in urinary tract and blood isolates of E. coli compared to fecal isolates. Last, the expression of ArtJ, an arginine periplasmic binding protein, is increased a mean of 16.6-fold in urine. This finding implicates arginine concentrations as limited in urine and, in combination with previous data demonstrating that argC is important for urovirulence, suggests that the ability of E. coli to synthesize or acquire arginine is important for urovirulence. ure1, iroN(E. coli), and artJ all have increased expression in human blood and ascites relative to LB medium as well. The identification of these genes increases our understanding of regulatory signals present in human urine, blood, and ascites. Ure1, IroN(E. coli), and ArtJ also warrant further evaluation as virulence traits both within and outside the urinary tract.  相似文献   
1000.
This study is a follow-up study on broadly defined schizophrenic disorders. Patients were assessed standardized at the time of their first hospitalization (admission and discharge) and reassessed in an standardized manner 15 years later. The aim of the analyses presented here was to evaluate the frequency of patients with markedly expressed negative symptoms in terms of deficit syndrome and to analyze which of the variables assessed at the time of first hospitalization were predictive concerning deficit syndromes at follow-up. Results indicate that nearly one third of patients have developed a deficit syndrome 15 years after their first hospitalization. These patients are characterized by severe impairments in important areas of life, such as partnership or employment. Furthermore, apart from more pronounced negative symptoms, these patients also have more paranoid-hallucinatory symptoms than schizophrenic patients without deficit syndromes. Predictive signs for non-development of a deficit syndrome 15 years later were good global functioning, female gender, pronounced depressive symptoms and good treatment response concerning negative and paranoid-hallucinatory symptoms at first hospitalization. A longer duration of symptoms prior to first hospitalization, lack of a partnership, pronounced negative symptoms at admission and at discharge were predictive of developing a deficit syndrome. Results are discussed with regard to the literature and to methodological limitations.  相似文献   
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